In the Patriots’ 52-28 victory in Week 4 — a game the Bills led, 21-7, early in the third quarter — the Patriots quickly abandoned their base defense and went with their nickel and dime schemes on more than 70 percent of their snaps.

They may have benefited because Buffalo running backs Fred Jackson and C.J. Spiller were returning from injury. Spiller, who had a shoulder injury, was a surprise participant, and he played like he was hurt.

Both are healthy and effective now, to the point that the Texans were obviously more worried about the running backs than they were quarterback Ryan Fitzpatrick.

The Texans basically dared the Bills (3-5) to beat them through the air, and Fitzpatrick averaged just 6.2 yards per attempt.

Fitzpatrick, who loves to get rid of the ball as quickly as possible, did not threaten the Texans down the field.

He stayed with the short, quick underneath passes, which further played into the Texans’ strategy.

Expect the Patriots to be enticed by the opportunity to defend Buffalo with the strength of their defense — the front seven — and for the Bills to be better prepared for an answer than they were against the Texans.

A closer look at the Bills:

OFFENSE

Fitzpatrick, even with four interceptions, had his most successful game of the season by far against the Patriots the first time around in terms of yards (350; next closest was 239), yards per attempt (8.97, second to Chiefs game) and touchdowns (four). The Bills hit on seven pass plays of 20 or more yards against the Patriots, and Fitzpatrick missed several open receivers. He has been a popgun passer since seeing the Patriots, with yards per attempt of 4.85, 4.78, 6.43, and 6.29. His mechanics are what they are: wildly inconsistent . . . Wide receiver Stevie Johnson should be ready for the Patriots after dealing with a thigh bruise against the Texans. He is exceedingly dangerous and should be featured as much as possible. The Patriots held him to just two receptions on 10 targets through the good work of Sterling Moore (since released) and Devin McCourty (now at safety for the time being). Donald Jones had a 68-yard touchdown reception against the Patriots when safeties Patrick Chung and Steve Gregory botched the play. Jones looms as a big-play threat. Rookie T.J. Graham and Brad Smith have been nonfactors. Tight end Scott Chandler is solid . . . On the line, the Bills placed right tackle Erik Pears on injured reserve, which is probably a blessing because he didn’t play well against the Patriots. Chris Hairston is better at pass blocking but struggles in the run. Left tackle Cordy Glenn, left guard Andy Levitre, center Eric Wood, and right guard Kraig Urbik are playing solid. The whole line benefits from Fitzpatrick getting rid of the ball so quickly, probably too fast for the pass offense to really function. If the Patriots play a lot of sub package, expect the Bills to really try to feed Jackson and Spiller, who are very good. Spiller deserves more than the 13 touches he is averaging per game with his 7.2-yard rushing average and 9.8 yards per reception.

DEFENSE

The Bills have struggled up front (31st at 169.5 rushing yards per game), and now they’re dealing with some serious secondary issues as they get set to face Tom Brady, who was outstanding in completing 22 of 36 passes for 340 yards and three touchdowns in the first matchup. The Bills knew they were going to be without No. 2 cornerback Aaron Williams (thigh) this time, and then they had to put backup Terrence McGee (knee) on injured reserve Tuesday. That means besides impressive first-round pick Stephon Gilmore, Leodis McKelvin, Justin Rogers, and Ron Brooks will be forced into action. McKelvin had been relegated to mostly special teams after being a bust as a first-round pick in 2008. Brooks is a fourth-round pick who was active for the first time against the Texans but didn’t play. And Rogers, a seventh-round pick in 2011, has struggled as the nickel/dime back. The Bills do have Jairus Byrd at safety, who is pushing for a Pro Bowl spot. He’s been outstanding against the pass and the run. George Wilson is solid at the other safety spot, but is losing some time to Da’Norris Searcy . . . Expect to see the Bills play more than the six snaps of base defense they played against the Patriots the first time around, which led to New England rushing 40 times for 247 yards . . . The biggest reason the Bills are so bad against the rush is that defensive coordinator Dave Wannstedt doesn’t have the type of mammoth tackles to occupy blockers. Kyle Williams and Marcell Dareus are good, but they’re mismatches for the scheme against the run. They penetrate too much. Wannstedt’s scheme relies on the tackles to free up the linebackers, especially middle linebacker Kelvin Sheppard. With this group, a little bit of misdirection — which the Patriots used in spades — allows linemen to get out on the linebackers and open up huge holes. Fourth-round pick Nigel Bradham has taken over for Arthur Moats on the strong side, and Nick Barnett is still playing well at weak side. Bryan Scott is the sub linebacker . . . End Mario Williams has woken up, with three sacks in three games. Mark Anderson (knee) is out indefinitely, and has been replaced by the platoon of Chris Kelsay and Kyle Moore, who has some pop rushing the passer. Shawne Merriman has been invisible in a limited role.

SPECIAL TEAMS

Alex Carrington blocked a field goal against the Texans. Rian Lindell missed his first field goal attempt of the season from 37 yards out against Houston, but made his other three. Punter Shawn Powell has a big leg and has done well since the team waived veteran Brian Moorman. With the injuries in the secondary, it will be interesting to see if the Bills cut back on McKelvin’s kick-return duties, because he’s outstanding at both.